The project's main objective is to determine whether increases in senescent life expectancy in recent decades are accelerating or decelerating in developed countries. Longevity as measured by the conventional life expectancy at birth has risen for about two centuries in the developed world, but the pace of improvement is decelerating and there is considerable disagreement about future trends. Pessimists believe we are approaching limits to life expectancy. In contrast, optimists expect continued improvements with no limits because mortality rates at older ages are declining rapidly. These opposing views about the future are rooted in disagreement about recent trends in mortality. The proposed study will attempt to resolve this controversy by assessing recent trends in senescent life expectancy in 27 developed countries. Specific aims are: 1) Develop/identify a set of indicators of trends in senescent life expectancy. Five indicators are proposed: a) life expectancy at birth in the absence of non-senescent mortality. This will be considered the reference indicator;b) life expectancy at age 65;c) adjusted life expectancy at age 65;d) age shift in the force of mortality at ages 65+;and e) the adult mode of the life table distribution of death rates by age above age 65. 2) Obtain empirical estimates of trends in senescent life expectancy based on these five indicators. All empirical estimates will be derived from data in the Human Mortality Database for females and males in 27 populations for all available years after 1950. 3) Test three hypotheses about similarities and differences in trends in the five indicators since 1950. 4) Estimate trends in the variation in the age at senescent death and assess their impact on trends in senescent life expectancy. Project Narrative: Rapid aging of populations in the industrialized world has led to growing demand for more accurate projections of mortality and of the size of the population of elderly. The proposed research examines alternative indicators of trends in senescent life expectancy to shed light on the ongoing controversy about future trends in life expectancy at birth. This analysis is expected to result in more accurate estimates of current trends in senescent life expectancy thus providing the basis for more accurate and more robust long-range projections of mortality and of the future cost of pension and health care systems.